54 research outputs found
Comparison Between Spectral-Domain and Swept-Source Optical Coherence Tomography Angiographic Imaging of Choroidal Neovascularization
PURPOSE. The purpose of this study was to compare imaging of choroidal neovascularization (CNV) using swept-source (SS) and spectral-domain (SD) optical coherence tomography angiography (OCTA). METHODS. Optical coherence tomography angiography was performed using a 100-kHz SS-OCT instrument and a 68-kHz SD-OCTA instrument (Carl Zeiss Meditec, Inc.). Both 3 x 3-and 6 x 6-mm(2) scans were obtained on both instruments. The 3 x 3-mm(2) SS-OCTA scans consisted of 300 A-scans per B-scan at 300 B-scan positions, and the SD-OCTA scans consisted of 245 A-scans at 245 B-scan positions. The 6 x 6-mm(2) SS-OCTA scans consisted of 420 A-scans per B-scan at 420 B-scan positions, and the SD-OCTA scans consisted of 350 A-scans and 350 B-scan positions. B-scans were repeated four times at each position in the 3 x 3-mm(2) scans and twice in the 6 x 6-mm(2) scans. Choroidal neovascularization was excluded if not fully contained within the 3 x 3-mm(2) scans. The same algorithm was used to detect CNV on both instruments. Two graders outlined the CNV, and the lesion areas were compared between instruments. RESULTS. Twenty-seven consecutive eyes from 23 patients were analyzed. For the 3 x 3-mm(2) scans, the mean lesion areas for the SS-OCTA and SD-OCTA instruments were 1.17 and 1.01 mm(2), respectively (P = 0.047). For the 6 x 6-mm(2) scans, the mean lesion areas for the SS-OCTA and SD-OCTA instruments were 1.24 and 0.74 mm(2) (P = 0.003). CONCLUSIONS. The areas of CNV tended to be larger when imaged with SS-OCTA than with SD-OCTA, and this difference was greater for the 6 x 6-mm(2) scans.Carl Zeiss Meditec, Inc.National Eye InstituteResearch to Prevent Blindness, Inc. (New York, NY)National Eye Institute Center Core GrantCAPES Foundation, Ministry of Education of Brazil (Brasilia, Brazil)German Research FoundationUniv Miami, Miller Sch Med, Bascom Palmer Eye Inst, Dept Ophthalmol, Miami, FL 33136 USAUniv Fed Sao Paulo, Dept Ophthalmol, Sao Paulo, BrazilUniv Washington, Dept Bioengn, Seattle, WA 98195 USACarl Zeiss Meditec Inc, Adv Dev, Dublin, CA USAUniv Fed Sao Paulo, Dept Ophthalmol, Sao Paulo, BrazilNational Eye Institute: R01EY024158National Eye Institute Center Core Grant: P30EY014801German Research Foundation: SCHA 1869/1-1Web of Scienc
Automated Quantitation of Choroidal Neovascularization: A Comparison Study Between Spectral-Domain and Swept-Source OCT Angiograms
PURPOSE. To compare the lesion sizes of choroidal neovascularization (CNV) imaged with spectral-domain (SD) and swept-source (SS) optical coherence tomography angiography (OCTA) and measured using an automated detection algorithm. METHODS. Patients diagnosed with CNV were imaged by SD-OCTA and SS-OCTA systems using 3 x 3-mm and 6 x 6-mm scans. The complex optical microangiography (OMAG(C)) algorithm was used to generate the OCTA images. Optical coherence tomography A datasets for imaging CNV were derived by segmenting from the outer retina to 8 mu m below Bruch's membrane. An artifact removal algorithm was used to generate angiograms free of retinal vessel projection artifacts. An automated detection algorithm was developed to quantify the size of the CNV. Automated measurements were compared with manual measurements. Measurements from SD-OCTA and SS-OCTA instruments were compared as well. RESULTS. Twenty-seven eyes from 23 subjects diagnosed with CNV were analyzed. No significant differences were detected between manual and automatic measurements: SD-OCTA 3 x 3-mm (P = 0.61, paired t-test) and 6 x 6-mm (P = 0.09, paired t-test) scans and the SS-OCTA 3 x 3-mm (P = 0.41, paired t-test) and 6 x 6-mm (P = 0.16, paired t-test) scans. Bland-Altman analyses were performed to confirm the agreement between automatic and manual measurements. Mean lesion sizes were significantly larger for the SS-OCTA images compared with the SD-OCTA images: 3 3 3-mm scans (P = 0.011, paired sample t-test) and the 6 x 6-mm scans (P = 0.021, paired t-test). CONCLUSIONS. The automated algorithm measurements of CNV were in agreement with the hand-drawn measurements. On average, automated SS-OCTA measurements were larger than SD-OCTA measurements and consistent with the results from using hand-drawn measurements.Carl Zeiss Meditec, Inc. (Dublin, CA)National Eye InstituteResearch to Prevent Blindness, Inc., New York, New YorkNational Eye Institute Center Core GrantCAPES Foundation, Ministry of Education of Brazil, Brasilia-BrazilGerman Research Foundation (DFG)Research to Prevent BlindnessUniv Washington, Dept Bioengn, 3720 NE 15th Ave, Seattle, WA 98195 USAUniv Miami, Miller Sch Med, Bascom Palmer Eye Inst, Dept Ophthalmol, Miami, FL 33136 USAUniv Fed Sao Paulo, Dept Ophthalmol, Sao Paulo, BrazilCarl Zeiss Meditec Inc, Adv Dev, Dublin, CA USAUniv Washington, Dept Ophthalmol, 3720 NE 15th Ave, Seattle, WA 98195 USAUniv Fed Sao Paulo, Dept Ophthalmol, Sao Paulo, BrazilNational Eye Institute: R01EY024158National Eye Institute Center Core Grant: P30EY014801German Research Foundation (DFG): SCHA 1869/1-1Web of Scienc
Comparison of Drusen Area Detected by Spectral Domain Optical Coherence Tomography and Color Fundus Imaging
Citation: Yehoshua Z, Gregori G, Sadda SR, et al. Comparison of drusen area detected by spectral domain optical coherence tomography and color fundus imaging. Invest Ophthalmol Vis Sci. 2013;54;4:24294: -24344: . DOI:10.1167 PURPOSE. To compare the measurements of drusen area from manual segmentation of color fundus photographs with those generated by an automated algorithm designed to detect elevations of the retinal pigment epithelium (RPE) on spectral domain optical coherence tomography (SD-OCT) images. METHODS. Fifty eyes with drusen secondary to nonexudative age-related macular degeneration were enrolled. All eyes were imaged with a high-definition OCT instrument using a 200 3 200 A-scan raster pattern covering a 6 mm 3 6 mm area centered on the fovea. Digital color fundus images were taken on the same day. Drusen were traced manually on the fundus photos by graders at the Doheny Image Reading Center, whereas quantitative OCT measurements of drusen were obtained by using a fully automated algorithm. The color fundus images were registered to the OCT data set and measurements within corresponding 3-and 5-mm circles centered at the fovea were compared. . The mean differences between color images and the SD-OCT (color À SD-OCT) were 0.36 (60.93) (P ¼ 0.008) for the 3-mm circle and 1.26 (61.38) (P < 0.001) for the 5-mm circle measurements. Intraclass correlation coefficients of agreements for 3-and 5-mm measurements were 0.599 and 0.540, respectively. RESULTS. The mean areas (6SD [range CONCLUSIONS. There was only fair agreement between drusen area measurements obtained from SD-OCT images and color fundus photos. Drusen area measurements on color fundus images were larger than those with SD-OCT scans. This difference can be attributed to the fact that the OCT algorithm defines drusen in terms of RPE deformations above a certain threshold, and will not include small, flat drusen and subretinal drusenoid deposits. The two approaches provide complementary information about drusen
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Behandlungsansätze bei trockener AMD
Die altersabhängige Makuladegeneration (AMD) ist in den Industriestaaten der Hauptgrund irreversibler Erblindung bei Menschen über 60 Jahren [1]. Schätzungsweise etwa 30% der Erwachsenen über 75 Jahren weisen Zeichen einer AMD auf, von denen etwa 10% ein fortgeschrittenes oder spätes Stadium der Erkrankung zeigen [2]. Die große Mehrheit der AMD-Patienten haben die nicht-exsudative oder trockene Form der Erkrankung, charakterisiert durch eine Konstellation bestimmter klinischer Zeichen, einschließlich Drusen, Pigmentanomalien (fokale Hyperoder Hypopigmentierungen des retinalen Pigmentepithels (RPE)) und geographischer Atrophie (GA) der Makula. Wie in der Age-Related Eye Disease Studie (AREDS) definiert, kann der Schweregrad der AMD in drei Kategorien eingeteilt werden: früh, intermediär und fortgeschritten
Reactivation of the Levant passive margin during the late Tertiary and formation of the Jaffa Basin offshore central Israel
Current Clinical Trials in Dry AMD and the Definition of Appropriate Clinical Outcome Measures
Currently, there is no proven drug treatment for dry age-related macular degeneration (AMD). Several different treatment strategies are being investigated, including complement inhibition, neuroprotection, and visual cycle inhibitors, and novel clinical trial endpoints are being explored. Studies have identified genetic predispositions for dry AMD associated with complement dysfunction. Consequently, complement-based therapeutic treatment modalities are promising
Spectral domain optical coherence tomography imaging of dry age-related macular degeneration
Spectral domain optical coherence tomography is a useful new technology for imaging and measuring geographic atrophy (GA) and drusen, the hallmarks of dry age-related macular degeneration (AMD). The advantage of using this novel technique over other imaging modalities for dry AMD is that the same scan pattern can be used to image both drusen and GA while obtaining reproducible, quantitative data on both the area of GA and the morphologic features of drusen. Moreover, this strategy enables the clinician to follow the disease as it progresses from drusen to both GA and choroidal neovascularization. No other imaging modality is able to quantitatively assess all forms of AMD. This unique feature of spectral domain optical coherence tomography makes it the ideal imaging modality for clinical trials designed to assess new drugs for the treatment of dry AMD
Anatomic Clinical Trial Endpoints for Nonexudative Age-Related Macular Degeneration
To review the role of anatomic endpoints in clinical trials for the study of nonexudative age-related macular degeneration (AMD) with an emphasis on a novel composite endpoint for the study of emerging therapies for intermediate AMD (iAMD).
Unlike clinical trials for exudative AMD, it is impractical to use the change in visual acuity (VA) as a primary endpoint for the study of nonexudative AMD. By the time VA has been lost in nonexudative AMD, proof-of-concept early-stage clinical trials would take years to run, and drug development would be a near impossible task. Surrogate endpoints are needed that reliably predict future vision loss and can be easily measured. Anatomic changes that correlate with disease progression in nonexudative AMD offer the greatest promise as primary endpoints.
In preparation for this review, the electronic PubMed database was searched for relevant research pertaining to anatomic endpoints for the study of nonexudative AMD. Paper selection was based on our knowledge of the field with the goal to be as inclusive as possible. Whenever possible, recent review articles and results from large clinical trials, preferably with outcomes from many years of follow-up were favored over trials of short duration.
The most commonly used anatomic endpoint for the study of late, nonexudative AMD is the growth of geographic atrophy (GA). The advantages of studying GA include the appreciation that its enlargement through the foveal center leads to significant vision loss through the availability of natural history studies, the understanding that prevention of this growth would preserve vision in the future, the ability to reliably measure GA using different imaging strategies, and the development appropriate statistical tools that reliably predict the growth of GA over time. The major disadvantage of using GA is that significant, irreversible disease progression has already occurred. The use of drusen volume as a predictor of disease progression and the use of a composite endpoint that incorporates drusen growth, formation of GA, and formation of neovascularization offers an opportunity to study therapies at an earlier stage of AMD with a greater likelihood of preserving better vision over a lifetime.
Anatomic endpoints for the study of nonexudative AMD are needed to accelerate drug development, and the availability of optical coherence tomography algorithms capable of reliably measuring drusen morphology offer the best opportunity to study therapies for iAMD
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Identifying the boundaries of retinal pigment epithelial detachments using two spectral-domain optical coherence tomography instruments
To compare two spectral-domain optical coherence tomography (SD-OCT) instruments in identifying the boundaries of retinal pigment epithelium detachment (PED).
27 eyes were scanned with Cirrus and Spectralis SD-OCT instruments during a single visit. Two Cirrus scan patterns were used: the 512 × 128 and 200 × 200 covering a 6 × 6 mm (20° × 20°) area. The Spectralis scan pattern consisted of seven B-scans, averaged 51 times, covering a 30° × 5° area. The main outcome measures were the retinal thickness at the foveal center and the number of segmentation failures on the central B-scan.
The Spectralis algorithm failed to follow the proper retinal contour in 25 eyes (92.6%), while the segmentation on the Cirrus instrument was successful in every central B-scan. Spectralis yielded greater retinal thickness measurements in all cases, and the average difference between Cirrus and Spectralis was 139 μm (P < .001). The intraclass correlation coefficient between the two Cirrus scan patterns was 0.998, and Cirrus versus Spectralis was 0.21.
The Cirrus SD-OCT instrument identifies the appropriate segmentation boundaries in the presence PED. The Spectralis SD-OCT algorithm was unreliable in segmenting PEDs, leading to inaccurate retinal thickness measurements unless manual adjustments were performed
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Purtscher-Like Retinopathy and Diffuse Alveolar Hemorrhage Caused by Soft Tissue Injection for Gluteal Augmentation
To describe a rare occurrence of acute vision loss and diffuse alveolar hemorrhage following a treatment of injectable gluteal cosmetic filler.
A 20-year-old female underwent a cosmetic injection of unknown components for gluteal augmentation. Within hours she developed progressive shortness of breath secondary to diffuse alveolar hemorrhage. She presented to ophthalmology 6 weeks later with a history of bilateral decreased vision. Clinical examination revealed cotton wool spots and retinal hemorrhages. Fluorescein angiography demonstrated macular vascular pruning and an enlarged foveal avascular zone.
The patient was observed and vision did not improve after 8 months of follow-up.
These findings were attributed to a Purtscher-like retinopathy secondary to systemic inflammation induced by the filler and/or direct microembolization of the injected material or fat. To the best of the authors' knowledge, this is the first documented case of diffuse alveolar hemorrhage and ischemic bilateral vision loss in a patient undergoing gluteal augmentation with dermal filler
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